X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FSjLjEHPrepare.cpp;h=7f46a062fa7b8ab1252bbb9a12af7d8c39f428b3;hb=a4b5050cf5af18ac18565073fecbfcb95f93556b;hp=5d60bc9b751abc76f8c3fbd2a64329c16187b441;hpb=20c918dfed5830f6d0c54c9c38817bd660cb6a13;p=oota-llvm.git diff --git a/lib/CodeGen/SjLjEHPrepare.cpp b/lib/CodeGen/SjLjEHPrepare.cpp index 5d60bc9b751..7f46a062fa7 100644 --- a/lib/CodeGen/SjLjEHPrepare.cpp +++ b/lib/CodeGen/SjLjEHPrepare.cpp @@ -1,4 +1,4 @@ -//===- SjLjEHPass.cpp - Eliminate Invoke & Unwind instructions -----------===// +//===- SjLjEHPrepare.cpp - Eliminate Invoke & Unwind instructions ---------===// // // The LLVM Compiler Infrastructure // @@ -13,26 +13,28 @@ //===----------------------------------------------------------------------===// #define DEBUG_TYPE "sjljehprepare" -#include "llvm/Transforms/Scalar.h" #include "llvm/Constants.h" #include "llvm/DerivedTypes.h" +#include "llvm/IRBuilder.h" #include "llvm/Instructions.h" #include "llvm/Intrinsics.h" #include "llvm/LLVMContext.h" #include "llvm/Module.h" #include "llvm/Pass.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SetVector.h" +#include "llvm/ADT/SmallPtrSet.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/Statistic.h" #include "llvm/CodeGen/Passes.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetData.h" #include "llvm/Target/TargetLowering.h" +#include "llvm/Transforms/Scalar.h" #include "llvm/Transforms/Utils/BasicBlockUtils.h" #include "llvm/Transforms/Utils/Local.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/IRBuilder.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/SmallPtrSet.h" -#include "llvm/ADT/SmallVector.h" -#include "llvm/ADT/Statistic.h" #include using namespace llvm; @@ -40,7 +42,7 @@ STATISTIC(NumInvokes, "Number of invokes replaced"); STATISTIC(NumSpilled, "Number of registers live across unwind edges"); namespace { - class SjLjEHPass : public FunctionPass { + class SjLjEHPrepare : public FunctionPass { const TargetLowering *TLI; Type *FunctionContextTy; Constant *RegisterFn; @@ -53,10 +55,10 @@ namespace { Value *PersonalityFn; Constant *CallSiteFn; Constant *FuncCtxFn; - Value *CallSite; + AllocaInst *FuncCtx; public: static char ID; // Pass identification, replacement for typeid - explicit SjLjEHPass(const TargetLowering *tli = NULL) + explicit SjLjEHPrepare(const TargetLowering *tli = NULL) : FunctionPass(ID), TLI(tli) { } bool doInitialization(Module &M); bool runOnFunction(Function &F); @@ -68,22 +70,24 @@ namespace { private: bool setupEntryBlockAndCallSites(Function &F); + void substituteLPadValues(LandingPadInst *LPI, Value *ExnVal, + Value *SelVal); Value *setupFunctionContext(Function &F, ArrayRef LPads); void lowerIncomingArguments(Function &F); void lowerAcrossUnwindEdges(Function &F, ArrayRef Invokes); - void insertCallSiteStore(Instruction *I, int Number, Value *CallSite); + void insertCallSiteStore(Instruction *I, int Number); }; } // end anonymous namespace -char SjLjEHPass::ID = 0; +char SjLjEHPrepare::ID = 0; -// Public Interface To the SjLjEHPass pass. -FunctionPass *llvm::createSjLjEHPass(const TargetLowering *TLI) { - return new SjLjEHPass(TLI); +// Public Interface To the SjLjEHPrepare pass. +FunctionPass *llvm::createSjLjEHPreparePass(const TargetLowering *TLI) { + return new SjLjEHPrepare(TLI); } // doInitialization - Set up decalarations and types needed to process // exceptions. -bool SjLjEHPass::doInitialization(Module &M) { +bool SjLjEHPrepare::doInitialization(Module &M) { // Build the function context structure. // builtin_setjmp uses a five word jbuf Type *VoidPtrTy = Type::getInt8PtrTy(M.getContext()); @@ -119,12 +123,20 @@ bool SjLjEHPass::doInitialization(Module &M) { /// insertCallSiteStore - Insert a store of the call-site value to the /// function context -void SjLjEHPass::insertCallSiteStore(Instruction *I, int Number, - Value *CallSite) { +void SjLjEHPrepare::insertCallSiteStore(Instruction *I, int Number) { + IRBuilder<> Builder(I); + + // Get a reference to the call_site field. + Type *Int32Ty = Type::getInt32Ty(I->getContext()); + Value *Zero = ConstantInt::get(Int32Ty, 0); + Value *One = ConstantInt::get(Int32Ty, 1); + Value *Idxs[2] = { Zero, One }; + Value *CallSite = Builder.CreateGEP(FuncCtx, Idxs, "call_site"); + + // Insert a store of the call-site number ConstantInt *CallSiteNoC = ConstantInt::get(Type::getInt32Ty(I->getContext()), Number); - // Insert a store of the call-site number - new StoreInst(CallSiteNoC, CallSite, true, I); // volatile + Builder.CreateStore(CallSiteNoC, CallSite, true/*volatile*/); } /// MarkBlocksLiveIn - Insert BB and all of its predescessors into LiveBBs until @@ -137,9 +149,41 @@ static void MarkBlocksLiveIn(BasicBlock *BB, MarkBlocksLiveIn(*PI, LiveBBs); } +/// substituteLPadValues - Substitute the values returned by the landingpad +/// instruction with those returned by the personality function. +void SjLjEHPrepare::substituteLPadValues(LandingPadInst *LPI, Value *ExnVal, + Value *SelVal) { + SmallVector UseWorkList(LPI->use_begin(), LPI->use_end()); + while (!UseWorkList.empty()) { + Value *Val = UseWorkList.pop_back_val(); + ExtractValueInst *EVI = dyn_cast(Val); + if (!EVI) continue; + if (EVI->getNumIndices() != 1) continue; + if (*EVI->idx_begin() == 0) + EVI->replaceAllUsesWith(ExnVal); + else if (*EVI->idx_begin() == 1) + EVI->replaceAllUsesWith(SelVal); + if (EVI->getNumUses() == 0) + EVI->eraseFromParent(); + } + + if (LPI->getNumUses() == 0) return; + + // There are still some uses of LPI. Construct an aggregate with the exception + // values and replace the LPI with that aggregate. + Type *LPadType = LPI->getType(); + Value *LPadVal = UndefValue::get(LPadType); + IRBuilder<> + Builder(llvm::next(BasicBlock::iterator(cast(SelVal)))); + LPadVal = Builder.CreateInsertValue(LPadVal, ExnVal, 0, "lpad.val"); + LPadVal = Builder.CreateInsertValue(LPadVal, SelVal, 1, "lpad.val"); + + LPI->replaceAllUsesWith(LPadVal); +} + /// setupFunctionContext - Allocate the function context on the stack and fill /// it with all of the data that we know at this point. -Value *SjLjEHPass:: +Value *SjLjEHPrepare:: setupFunctionContext(Function &F, ArrayRef LPads) { BasicBlock *EntryBB = F.begin(); @@ -148,71 +192,42 @@ setupFunctionContext(Function &F, ArrayRef LPads) { // because the value needs to be added to the global context list. unsigned Align = TLI->getTargetData()->getPrefTypeAlignment(FunctionContextTy); - AllocaInst *FuncCtx = + FuncCtx = new AllocaInst(FunctionContextTy, 0, Align, "fn_context", EntryBB->begin()); // Fill in the function context structure. - Value *Idxs[2]; - Type *Int32Ty = Type::getInt32Ty(F.getContext()); - Value *Zero = ConstantInt::get(Int32Ty, 0); - Value *One = ConstantInt::get(Int32Ty, 1); - - // Keep around a reference to the call_site field. - Idxs[0] = Zero; - Idxs[1] = One; - CallSite = GetElementPtrInst::Create(FuncCtx, Idxs, "call_site", - EntryBB->getTerminator()); - - // Reference the __data field. - Idxs[1] = ConstantInt::get(Int32Ty, 2); - Value *FCData = GetElementPtrInst::Create(FuncCtx, Idxs, "__data", - EntryBB->getTerminator()); - - // The exception value comes back in context->__data[0]. - Idxs[1] = Zero; - Value *ExceptionAddr = GetElementPtrInst::Create(FCData, Idxs, - "exception_gep", - EntryBB->getTerminator()); - - // The exception selector comes back in context->__data[1]. - Idxs[1] = One; - Value *SelectorAddr = GetElementPtrInst::Create(FCData, Idxs, - "exn_selector_gep", - EntryBB->getTerminator()); - for (unsigned I = 0, E = LPads.size(); I != E; ++I) { LandingPadInst *LPI = LPads[I]; IRBuilder<> Builder(LPI->getParent()->getFirstInsertionPt()); + // Reference the __data field. + Value *FCData = Builder.CreateConstGEP2_32(FuncCtx, 0, 2, "__data"); + + // The exception values come back in context->__data[0]. + Value *ExceptionAddr = Builder.CreateConstGEP2_32(FCData, 0, 0, + "exception_gep"); Value *ExnVal = Builder.CreateLoad(ExceptionAddr, true, "exn_val"); - ExnVal = Builder.CreateIntToPtr(ExnVal, Type::getInt8PtrTy(F.getContext())); - Value *SelVal = Builder.CreateLoad(SelectorAddr, true, "exn_selector_val"); + ExnVal = Builder.CreateIntToPtr(ExnVal, Builder.getInt8PtrTy()); - Type *LPadType = LPI->getType(); - Value *LPadVal = UndefValue::get(LPadType); - LPadVal = Builder.CreateInsertValue(LPadVal, ExnVal, 0, "lpad.val"); - LPadVal = Builder.CreateInsertValue(LPadVal, SelVal, 1, "lpad.val"); + Value *SelectorAddr = Builder.CreateConstGEP2_32(FCData, 0, 1, + "exn_selector_gep"); + Value *SelVal = Builder.CreateLoad(SelectorAddr, true, "exn_selector_val"); - LPI->replaceAllUsesWith(LPadVal); + substituteLPadValues(LPI, ExnVal, SelVal); } // Personality function - Idxs[1] = ConstantInt::get(Int32Ty, 3); + IRBuilder<> Builder(EntryBB->getTerminator()); if (!PersonalityFn) PersonalityFn = LPads[0]->getPersonalityFn(); - Value *PersonalityFieldPtr = - GetElementPtrInst::Create(FuncCtx, Idxs, "pers_fn_gep", - EntryBB->getTerminator()); - new StoreInst(PersonalityFn, PersonalityFieldPtr, true, - EntryBB->getTerminator()); + Value *PersonalityFieldPtr = Builder.CreateConstGEP2_32(FuncCtx, 0, 3, + "pers_fn_gep"); + Builder.CreateStore(PersonalityFn, PersonalityFieldPtr, /*isVolatile=*/true); // LSDA address - Idxs[1] = ConstantInt::get(Int32Ty, 4); - Value *LSDAFieldPtr = GetElementPtrInst::Create(FuncCtx, Idxs, "lsda_gep", - EntryBB->getTerminator()); - Value *LSDA = CallInst::Create(LSDAAddrFn, "lsda_addr", - EntryBB->getTerminator()); - new StoreInst(LSDA, LSDAFieldPtr, true, EntryBB->getTerminator()); + Value *LSDA = Builder.CreateCall(LSDAAddrFn, "lsda_addr"); + Value *LSDAFieldPtr = Builder.CreateConstGEP2_32(FuncCtx, 0, 4, "lsda_gep"); + Builder.CreateStore(LSDA, LSDAFieldPtr, /*isVolatile=*/true); return FuncCtx; } @@ -221,7 +236,7 @@ setupFunctionContext(Function &F, ArrayRef LPads) { /// specially, we lower each arg to a copy instruction in the entry block. This /// ensures that the argument value itself cannot be live out of the entry /// block. -void SjLjEHPass::lowerIncomingArguments(Function &F) { +void SjLjEHPrepare::lowerIncomingArguments(Function &F) { BasicBlock::iterator AfterAllocaInsPt = F.begin()->begin(); while (isa(AfterAllocaInsPt) && isa(cast(AfterAllocaInsPt)->getArraySize())) @@ -265,8 +280,8 @@ void SjLjEHPass::lowerIncomingArguments(Function &F) { /// lowerAcrossUnwindEdges - Find all variables which are alive across an unwind /// edge and spill them. -void SjLjEHPass::lowerAcrossUnwindEdges(Function &F, - ArrayRef Invokes) { +void SjLjEHPrepare::lowerAcrossUnwindEdges(Function &F, + ArrayRef Invokes) { // Finally, scan the code looking for instructions with bad live ranges. for (Function::iterator BB = F.begin(), BBE = F.end(); BB != BBE; ++BB) { @@ -320,6 +335,8 @@ void SjLjEHPass::lowerAcrossUnwindEdges(Function &F, for (unsigned i = 0, e = Invokes.size(); i != e; ++i) { BasicBlock *UnwindBlock = Invokes[i]->getUnwindDest(); if (UnwindBlock != BB && LiveBBs.count(UnwindBlock)) { + DEBUG(dbgs() << "SJLJ Spill: " << *Inst << " around " + << UnwindBlock->getName() << "\n"); NeedsSpill = true; break; } @@ -361,16 +378,16 @@ void SjLjEHPass::lowerAcrossUnwindEdges(Function &F, /// setupEntryBlockAndCallSites - Setup the entry block by creating and filling /// the function context and marking the call sites with the appropriate /// values. These values are used by the DWARF EH emitter. -bool SjLjEHPass::setupEntryBlockAndCallSites(Function &F) { +bool SjLjEHPrepare::setupEntryBlockAndCallSites(Function &F) { SmallVector Returns; SmallVector Invokes; - SmallVector LPads; + SmallSetVector LPads; // Look through the terminators of the basic blocks to find invokes. for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) if (InvokeInst *II = dyn_cast(BB->getTerminator())) { Invokes.push_back(II); - LPads.push_back(II->getUnwindDest()->getLandingPadInst()); + LPads.insert(II->getUnwindDest()->getLandingPadInst()); } else if (ReturnInst *RI = dyn_cast(BB->getTerminator())) { Returns.push_back(RI); } @@ -382,55 +399,39 @@ bool SjLjEHPass::setupEntryBlockAndCallSites(Function &F) { lowerIncomingArguments(F); lowerAcrossUnwindEdges(F, Invokes); - Value *FuncCtx = setupFunctionContext(F, LPads); + Value *FuncCtx = + setupFunctionContext(F, makeArrayRef(LPads.begin(), LPads.end())); BasicBlock *EntryBB = F.begin(); - Type *Int32Ty = Type::getInt32Ty(F.getContext()); - - Value *Idxs[2] = { - ConstantInt::get(Int32Ty, 0), 0 - }; + IRBuilder<> Builder(EntryBB->getTerminator()); // Get a reference to the jump buffer. - Idxs[1] = ConstantInt::get(Int32Ty, 5); - Value *JBufPtr = GetElementPtrInst::Create(FuncCtx, Idxs, "jbuf_gep", - EntryBB->getTerminator()); + Value *JBufPtr = Builder.CreateConstGEP2_32(FuncCtx, 0, 5, "jbuf_gep"); // Save the frame pointer. - Idxs[1] = ConstantInt::get(Int32Ty, 0); - Value *FramePtr = GetElementPtrInst::Create(JBufPtr, Idxs, "jbuf_fp_gep", - EntryBB->getTerminator()); + Value *FramePtr = Builder.CreateConstGEP2_32(JBufPtr, 0, 0, "jbuf_fp_gep"); - Value *Val = CallInst::Create(FrameAddrFn, - ConstantInt::get(Int32Ty, 0), - "fp", - EntryBB->getTerminator()); - new StoreInst(Val, FramePtr, true, EntryBB->getTerminator()); + Value *Val = Builder.CreateCall(FrameAddrFn, Builder.getInt32(0), "fp"); + Builder.CreateStore(Val, FramePtr, /*isVolatile=*/true); // Save the stack pointer. - Idxs[1] = ConstantInt::get(Int32Ty, 2); - Value *StackPtr = GetElementPtrInst::Create(JBufPtr, Idxs, "jbuf_sp_gep", - EntryBB->getTerminator()); + Value *StackPtr = Builder.CreateConstGEP2_32(JBufPtr, 0, 2, "jbuf_sp_gep"); - Val = CallInst::Create(StackAddrFn, "sp", EntryBB->getTerminator()); - new StoreInst(Val, StackPtr, true, EntryBB->getTerminator()); + Val = Builder.CreateCall(StackAddrFn, "sp"); + Builder.CreateStore(Val, StackPtr, /*isVolatile=*/true); // Call the setjmp instrinsic. It fills in the rest of the jmpbuf. - Value *SetjmpArg = CastInst::Create(Instruction::BitCast, JBufPtr, - Type::getInt8PtrTy(F.getContext()), "", - EntryBB->getTerminator()); - CallInst::Create(BuiltinSetjmpFn, SetjmpArg, "", EntryBB->getTerminator()); + Value *SetjmpArg = Builder.CreateBitCast(JBufPtr, Builder.getInt8PtrTy()); + Builder.CreateCall(BuiltinSetjmpFn, SetjmpArg); // Store a pointer to the function context so that the back-end will know // where to look for it. - Value *FuncCtxArg = CastInst::Create(Instruction::BitCast, FuncCtx, - Type::getInt8PtrTy(F.getContext()), "", - EntryBB->getTerminator()); - CallInst::Create(FuncCtxFn, FuncCtxArg, "", EntryBB->getTerminator()); + Value *FuncCtxArg = Builder.CreateBitCast(FuncCtx, Builder.getInt8PtrTy()); + Builder.CreateCall(FuncCtxFn, FuncCtxArg); // At this point, we are all set up, update the invoke instructions to mark // their call_site values. for (unsigned I = 0, E = Invokes.size(); I != E; ++I) { - insertCallSiteStore(Invokes[I], I + 1, CallSite); + insertCallSiteStore(Invokes[I], I + 1); ConstantInt *CallSiteNum = ConstantInt::get(Type::getInt32Ty(F.getContext()), I + 1); @@ -449,9 +450,9 @@ bool SjLjEHPass::setupEntryBlockAndCallSites(Function &F) { for (BasicBlock::iterator I = BB->begin(), end = BB->end(); I != end; ++I) if (CallInst *CI = dyn_cast(I)) { if (!CI->doesNotThrow()) - insertCallSiteStore(CI, -1, CallSite); + insertCallSiteStore(CI, -1); } else if (ResumeInst *RI = dyn_cast(I)) { - insertCallSiteStore(RI, -1, CallSite); + insertCallSiteStore(RI, -1); } // Register the function context and make sure it's known to not throw @@ -486,7 +487,7 @@ bool SjLjEHPass::setupEntryBlockAndCallSites(Function &F) { return true; } -bool SjLjEHPass::runOnFunction(Function &F) { +bool SjLjEHPrepare::runOnFunction(Function &F) { bool Res = setupEntryBlockAndCallSites(F); return Res; }